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Fraction

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Fraction

Fig: Fraction
Fig: Fraction
source:www.mathsisfun.com


A fraction is a number which is usually expressed in the form of \(\frac{a}{b}\). For examples ( \(\frac{3}{4}\), \(\frac{5}{3}\), \(\frac{9}{7}\), etc.)

Comparison of fraction

A fraction can be compared to their likes and unlike terms. We can compare like fractions by comparing their numerators and to compare unlike fractions, we should convert them into like fractions. By comparing those like fractions, as a result, we can find greater and the smaller fraction. For example, Let's compare \(\frac{5}{3}\) and \(\frac{7}{4}\)

Here, the L.C.M of denominators 3 and 4 = 3×4 = 12

Now, \(\frac{5}{3}\) = \(\frac{5×4}{3×4}\) = \(\frac{20}{12}\)

And, \(\frac{7×3}{4×3}\) = \(\frac{21}{12}\)

Here, \(\frac{21}{12}\) > \(\frac{20}{12}\), So, \(\frac{7}{3}\) > \(\frac{4}{3}\)

Addition and Substraction of Fraction

Fig: Addition and Subtraction of Fraction
Fig: Addition and Subtraction of Fraction
source:math.info

If the like fraction is given, we can add or substract them just by adding or substracting their numenator. For example, \(\frac{5}{6}\) + \(\frac{7}{6}\) = \(\frac{12}{6}\) = 2

\(\frac{10}{7}\) - \(\frac{9}{7}\) = \(\frac{10 - 9}{7}\) = \(\frac{1}{7}\) ans.

In case of unlike fraction, at first we should convert them into like fractions with the least common denominator, then we add or substract their numenator. For example,

or,\(\frac{4}{5}\) - \(\frac{3}{7}\) = \(\frac{4 × 7}{5 × 7}\) - \(\frac{3 × 5}{7 × 5}\)

= \(\frac{21}{35}\) - \(\frac{15}{35}\)

= \(\frac{21 -15}{35}\)

= \(\frac{6}{35}\) ans.

Multiplication of fraction

Fig: Multiplication of Fraction
Fig: Multiplication of Fraction
source:www.ducksters.com

Multiplication of fraction can be done by the product of a whole number and a fraction as well as product of a two fraction. For example 3× \(\frac{4}{3}\)

\(\frac{3}{1}\) × \(\frac{4}{3}\) = \(\frac{12}{3}\) =4

\(\frac{1}{3}\) × \(\frac{6}{5}\) = \(\frac{1×6}{3×5}\) = \(\frac{6}{15}\) = \(\frac{2}{5}\) ans.

Division of fraction

Fig: Division of Fraction
Fig: Division of Fraction
source:cribbd.com

To divide a whole number by a fraction, we should multiply the whole number by the reciprocal of the fraction. For example,

4÷ \(\frac{1}{6}\) = 4× \(\frac{1}{6}\) = \(\frac{4}{6}\) = \(\frac{2}{3}\) ans.



  • To divide a whole number by a fraction, we should multiply the whole number by the reciprocal of the fraction.
  • By comparing those like fractions, as a result, we can find greater and the smaller fraction. 
.

Very Short Questions

Solution:

Let the required sum be x.

Now, \(\frac{2}{7}\) of x = Rs. 120

or, \(\frac{2}{7}\) × x = Rs. 120

or, 2x = 7 × Rs. 120

or, x = \(\frac{7 × Rs. 120}{2}\)

 = Rs. 420

So the required sum is Rs. 420.

Solution:

Let, he had x l of milk in the begining.

Remaining parts of the quantity of milk = 1 - \(\frac{3}{4}\) = \(\frac{1}{4}\) part.

Now, \(\frac{1}{4}\) of x = 15 l

or, \(\frac{1}{4}\) × x = 15 l

or, x = 4 × 15 l = 60 l

So, he had 60 l of milk in the begining.

Solution:

In 1 day, Kamala can do \(\frac{1}{12}\) part of a piece of work.

In 3 days, Kamala can do 3 × \(\frac{1}{12}\) part of work = \(\frac{1}{4}\) parts of a piece of work

Now, the remaining parts of the work done by Reeta = (1-\(\frac{1}{4}\)) = \(\frac{3}{4}\) parts.

So, \(\frac{3}{4}\) parts of the work is done by Reeta.

0%
  • What is the sum, if (frac{2}{7}) of a sum is Rs. 120?

    520
    320
    400
    420
  • What is the value if (frac{3}{5}) of Rs. 750?

    400
    450
    400
    550
  • What is the fraction of decimal 0.45?

    (frac{9}{20})
    (frac{9}{15})
    (frac{8}{15})
    (frac{8}{20})
  • What is the fraction of decimal 0.3?

    (frac{2}{3})
    (frac{3}{2})
    (frac{4}{3})
    (frac{1}{3})
  • A man had some milk. When he sold (frac{3}{4}) parts of the quantity of milk, 15 litres was left. How much milk did he have in the beginning?

    65 litrs
    60 litres
    50 litres
    55 litres
  • What will be the sum if (frac{1}{4}) part of the sum is Rs. 75?

    Rs. 400
    Rs. 500
    Rs. 300
    Rs. 200
  • If a girl obtained 32.8 marks in Nepali and failed by 7.2 marks, then what was the pass marks of the subject?

    45
    35
    40
    32.5
  • The circumference of the wheel of a bus is 2.8 m. How many revolutions does ir make to cover 3.5 km?

    1350
    1050
    1250
    1150
  • Simplify : (frac{2}{3}) + (frac{3}{4})

    1(frac{4}{7})
    (frac{6}{7})
    1(frac{5}{12})
    (frac{6}{12})
  • Simplify : (frac{5}{6}) -  (frac{3}{7})

    (frac{15}{36})
    (frac{2}{-1})
    (frac{17}{42})
    (frac{8}{13})
  • Simplify : 5 - (frac{2}{3})

    3(frac{2}{3})
    2(frac{2}{3})
    1(frac{2}{3})
    4(frac{2}{3})
  • Simplify : 8 × (frac{3}{4})

    5
    7
    8
    6
  • Simplify : (frac{7}{9}) × 15

    3(frac{4}{3})
    2(frac{5}{7})
    1(frac{2}{3})
    11(frac{2}{3})
  • Simplify : (frac{6}{5}) ÷ (frac{8}{15})

    1(frac{2}{3})
    2(frac{1}{4})
    2(frac{2}{3})
    1(frac{1}{2})
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